This invention relates to television systems and is particularly concerned with means for enhancing the utility of the standard television receiver.
The use of the television receiver has been limited largely to its original purpose, which is to serve as a channel for broadcast television programming primarily for entertainment. The television receiver, however, has the potential to become a great deal more useful and important. The television receiver, which conveys both picture and sound, is a resource of immense potential because of its inherent capability in presenting complex video and audio information, and for its potential for interacting with other systems such as computers and video tape recorders. Another major and most significant benefit lies in the fact that there are so many television sets in use--most homes in the United States have at least one television set. So a basic capability with all its potential is to a great extent already in situ.
One of the most significant of the means for enhancing the potential of the receiver, is the remote control system by which the various functions of the receiver, such as ON-OFF, volume control, channel selection, mute, etc., can be controlled at a distance from the receiver. The remote control system commonly comprises a hand-held, battery-operated unit having a keypad including a numerical pad for control of the various functions. The link between the control and the receiver may be by wire, but more commonly, by signals such as radio frequency, ultrasonic or infra-red.
A recent and highly significant means for increasing the utility of the television receiver is disclosed in referent copending application Ser. No. 109,424 now U.S. Pat. No. 4,338,492 which discloses a television receiver comprising a cabinet housing a television system and a telephone network access circuit. The television receiver provides both for presentation of television programs and for conversing through the talk channel and listen channel of an associated telephone network. The receiver has at least one function control circuit including operational mode selection means for providing a television program mode, and alternately, a two-way telephone conversation mode. When the presence of a ringer signal from the telephone network is indicated, the television receiver user can activate the two-way telephone conversation mode and conduct a two-way conversation with the telephone caller through the television receiver. Upon termination of the conversation, the television receiver user can restore the television program mode. In referent copending application Ser. No. 175,456 now U.S. Pat. No. 4,349,701, a division of the aforesaid '424 application, there is disclosed a receiver providing for two-way telephone conversation with a dial-out facility.
Shaver et al in U.S. Pat. No. 3,816,662 discloses a combination telephone and video communication system for selectively enabling, from a given location in which a video terminal is provided, another video terminal at a desired one of a plurality of remote locations. Specifically, Shaver et al is concerned with an enabling arrangement in conjunction with intercom and door-answering systems for apartment buildings or the like. The purpose is to make it possible for the tenant in an apartment to converse with and to see a visitor calling from an entrance of the building.
King in U.S. Pat. No. 3,355,546 discloses a pay sound system for closed circuit television in which the audio component is conveyed via carrier current transmission. The system is intended for hotels, motels, community television services and other mass networks of television receivers which are connected by coaxial cable to central distribution amplifiers to which master antennas supply an input signal. The viewer may listen to the audio portion of a program by means of a conventional carrier current receiver tuned to a transmitted frequency. The receiver may be rented to the user on a time basis or it may be provided with a coin-controlled power input. The video information is routed to a plurality of television receivers by way of separate conductor. The intent appears to be to provide the viewer with the video information, but exact a charge for receiving the corollary audio information.
Tanner--U.S. Pat. No. 3,492,418 discloses a signal transmission system using DC control signals to selectively operate a television receiver as a monitor and to control an intercom system. The system is said to include a camera with one section of an audio intercom nearby. A television receiver and another section of the intercom are located at some distance from the camera. A switch near the receiver has a first position to connect the antenna to the receiver and to simultaneously turn off the camera and the intercom. A second section disconnects the antenna, connects the camera to the receiver, and turns the camera and intercom off. A cable connecting the camera to the receiver has a signal shielded conductor for transmission of the camera signal, the audio intercom signal and the power on-off control.